Aircraft are known that include devices for connecting the tires of wheels to an on-board pneumatic unit. The unit may be an air compressor, a nitrogen generator, or any other system enabling gas to be delivered under a pressure suitable for inflating the tires. Depending on whether the pressure made available by the pneumatic unit is greater than or less than the pressure that exists in the tire, the tire will inflate or deflate. When the aircraft is on the ground, the pneumatic unit can be connected to an external source of pressure.
Document GB 1 031 726 illustrates such a device, having some of its elements outside the axle. In particular, the wheel is fitted with a protective cover that covers the end of the axle and that receives an isolation valve of the tire. That disposition of the valve makes it sensitive to external impacts. Furthermore, the valve is actuated by a needle that is movable in an axial orifice of the axle. That type of device is not suitable for modern aircraft that usually have axles that are hollow. In addition, it includes a plurality of parts that are separately removable (the needle in the axle, the valve in the wheel cover), which does not facilitate maintenance thereof.
Document U.S. Pat. No. 2,107,405 and U.S. Pat. No. 2,685,906 disclose other devices, more particularly adapted to land vehicles. In particular, the device shown in document U.S. Pat. No. 2,685,906, which is in accordance with the introductory portion of claim 1, is found to be advantageous in that it is entirely modular and can be removed as a whole, naturally providing the gas connections are disconnected. Nevertheless, that device projects from the wheel and is therefore exposed to impacts.